Dell PowerVault 715N (Rackmount NAS Appliance) - Manual (Page 48)

Back to Contents Page
Dell ActiveArchive
Dell™ PowerVault™ 715N NAS Appliance System Administrator's Guide
Introduction to Persistent Images
Scheduling Persistent Images
Using Persistent Images
Accessing Stored Persistent Images in Dell ActiveArchive
Restoring Volumes From an Existing Persistent Image
Changing the Dell ActiveArchive Event Log Language
Dell ActiveArchive™ allows the creation and preservation of persistent images of Dell PowerVault™ 715N system data
volumes. The Dell ActiveArchive software is available for all PowerVault 715N systems. It can be configured by using the
NAS Manager.
This section provides information about the following topics:
Introduction to persistent images
Scheduling persistent images
Adding persistent images to the schedule
Deleting a persistent image schedule
Editing the properties of a persistent image schedule
Taking a new persistent image on demand
Deleting a persistent image
Undoing writes to a read/write persistent image
Configuring the persistent image global settings
Setting persistent image retention weights and read only or read/write attributes
Accessing store persistent images in Dell ActiveArchive
Restoring volumes from an existing persistent image
Introduction to Persistent Images
A persistent image is a point-in-time copy of a disk volume. Unlike conventional volumes, the information in the
persistent image is static. A persistent image contains an exact copy of the file system at the time the persistent image
was created. If you change a file on the active file system after taking a persistent image, the persistent image contains
the old version of the file. If an active file gets corrupted or deleted, you can restore the old version by copying the file
from the latest persistent image. Also, because the persistent image contains the contents of the file system when the
persistent image was taken, you can perform a backup from the persistent image without stopping all I/O to the file
servers, thus, eliminating the backup window required by other types of backup.
NOTICE: Persistent images are temporary backups of your data that reside on the same volume as your data. If
the volume becomes damaged, you lose your data, including the persistent image. Therefore, persistent images do
not replace regular backups of your volume.
Cache File
The Dell ActiveArchive software stores changed data in a cache file. A cache file resides on each volume of your system.
By default, the persistent image cache file is 20 percent of each volume. You can use the NAS Manager to change the
percentage of the volume that is dedicated to the cache file.